title: The rate of wound healing is increased in psoriasis.
abstract: BACKGROUND
  Psoriasis shares many features with wound healing, a process that involves switching keratinocytes from growth to differentiation. Ca2+ is known to regulate this process. The N-methyl-d-aspartate receptor (NMDAR), an ionotropic glutamate receptor found on keratinocytes, is expressed abnormally in psoriasis in vivo.
  
  
  OBJECTIVE
  The goals of this study are to determine whether the rate of healing in the skin of psoriatic individuals differs from that observed in normal skin and whether the keratinocyte hyperproliferation found in psoriasis correlates with expression of specific NMDAR subunits.
  
  
  METHODS
  Three mm punch biopsies were performed on the skin of normal, as well as, involved and uninvolved skin of subjects with psoriasis. On day 0, as well as, on day 6 after the biopsy, photographs were taken and the size of the wounds determined using ImageJ. Using immunohistochemistry, the biopsy material was stained for NMDAR and its subunits.
  
  
  RESULTS
  Involved and uninvolved skin of individuals with psoriasis shows significantly more rapid healing than normal. The NR2C subunit of NMDAR is down-regulated in the basal cell layer of involved and uninvolved epidermis of psoriatic subjects compared to controls. By contrast, cells in the basal cell layer of the uninvolved epidermis showed a significantly greater percent strong staining for NR2D compared to those cells in normal epidermis.
  
  
  CONCLUSIONS
  Wound healing is significantly accelerated in psoriasis compared to normal. Immunohistochemistry showed that the relative intensity of strong immunostaining for subunits of the NMDAR is altered in the basal cell layer in psoriatic skin compared to normal controls. We suggest that these alterations may contribute to the increased rate of wound healing in psoriasis.
authors.affiliation: Therapeutics Clinical Research, San Diego, CA, United States. Electronic address: morhennvera@yahoo.com.
authors.forename: V B
authors.initials: VB
authors.lastname: Morhenn
authors.forename: T E
authors.initials: TE
authors.lastname: Nelson
authors.forename: D L
authors.initials: DL
authors.lastname: Gruol
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002118:Calcium / Q000737:chemistry / Q000378:metabolism*; D002454:Cell Differentiation; D049109:Cell Proliferation; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000166:cytology; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000378:metabolism* / Q000503:physiopathology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D012867:Skin / Q000378:metabolism; D013997:Time Factors; D014945:Wound Healing
chemical_list: C432823:NR2C NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D002118:Calcium
keywords: Keratinocyte proliferation; NMDA-receptor; Psoriasis; Wound healing